java - 跳过从 PDF 读取的字节

Question

import java.io.*;
class BS{

    public void pStr(){
        try{
            String command="cat /usr/share/doc/bash/rbash.pdf";
            Process ps=Runtime.getRuntime().exec(command);
            InputStream in  = ps.getInputStream();
            int c;
            while((c=in.read())!=-1){
                System.out.print((char)c);
            }

        }catch(Exception e){
            e.printStackTrace();
        }

    }
    public static void main(String args[]){
        new BS().pStr();
    }
}

jabira-whosechild-lm.local 23:54:00 % java BS|wc 384 2003 43885

jabira-whosechild-lm.local 23:54:05 % wc /usr/share/doc/bash/rbash.pdf 384 2153 43885 /usr/share/doc/bash/rbash.pdf

Why do i see the difference in the number of characters that are read and printed to the console

Answer 1

方法InputStream.read()仅读取一个字节。

您的源代码行System.out.print((char)c);是错误的。调用方法 PrintStream.print(char c)，此方法为某些非 ASCII 字符值写入两个字节。

您需要调用一种始终写入一个字节值的方法。正确的方法是System.out.write(c);。